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NOV. 25., 19.46»
'
w. B. BRONANDER, JR I
'
VALVE
2,411,775
MEGHANISM
Filed'July 21, 1944
»f
/
31”” Jdf/ ff
INVENTOR
2,411,775.
Patented Nov. 26, 1946
UNITED As'irATrzs Partnr orties
`Wilhelm B. Eronander, Jr., Montclair, N. J.,
assigner otono-half to Wilhelm B. .Bronanden
Sr., Montclair, N. J.
ApplicationvJuly 21, 1944, Serial No..545,996 " .
' 1 Claim.
(Cl. 123-90)
»
2 .
This invention relates to valve -mechanisms for
internal combustion engines and particularly to
a method of balancing valve operating mecha
nisms.
y
In the standard valve actuating mechanism
thevva'lve is usually vactuated by a rocker arm vto
open the valve, the rocker Aarm being actuated
by suitable mechanism, such as a push rod, which
Fig. 1 is an elevational yview showing the valve
and valve mounting in section and illustrating
the valve operating mechanism in elevation, this
mechanism being constructedin accordance with
the invention; and
'
Fig. 2 is a top plan view, partly in section, of
apart of the structure shown in Fig. 1.
,
In the particular embodiment of the structure
for carrying out'the invention there is shown a
in turn is operated by 4a cam. Springs are pro
vided and operate on the valve stem to close the 10 portion `lil of a cylinder head having a valve
guide ii in which is mounted a reciprocatable
valve, return- the rocker arm `and push rod to
valve having a stem l2 and a head I3 which seats
their` initial or inoperative positions, and main
on a valve seat lll.
tain the push rod operating means in contact vwith
A spring l5 surrounds the valve stem and en
the cam. In case the valve freezes or sticks
gages
a ñxed Seat I6 at one end thereof and at
15
and does> not close, the valve spring action on
its opposite end engages the upper end l1 of
the rocker arm, push rod and tappet is suspended
the valve stern I2.
and the cam which operates the tappet-hammers
The valve is actuated by a rocker arm which
the tappet, causing serious damage.
is mounted on a pin 20 mounted in suitable bear
Internal combustion engines and particularly
aircraft engines are operated at very high speeds 20 ings and the rocker arm comprises an >arm 2|
having a roller 22 which engages the upper end
and this has resulted in putting a great strain
I1 of the valve stem and a rearwardly extending
~ on the valve mechanism and particularly on the
arm 23 having a pivot socket 24 for receiving >the
spring closing means. When the engine races
spherical upper end 25 of a push rod 26.
at high speed the inertia forces of the rocker arm,
The rocker has a hub 30 which is mounted on
25
push rod and tappet overpower the valve spring
a pair of sleeves 3i and 32, the inner sleeve being
and the tappet does not follow the cam, again
mounted on the pinv 2G which in turn is mounted
causing a hammering action to take place. As
in flanged bushings or bearings 33 and 34.
usually operated, this spring closing mechanismv
The lower> end of the push rod 26 is pivoted
is relied on to overcome the inertia of the rocker
arm and push rod as well as to close the valve. 30 at 35 to a cylindrical block 36 which is mounted
in a bearing 3'! and has mounted on its lower
This invention has for its salient object to
endl a roller 38 engaging a cam 39. As the cam
balance the reciprocating and oscillating inertia
3S is rotated the roller and block 35 are recipro
forces of the rocker arm and push rod, thereby
cated, thus actuating the push rod 28 and rocker
relieving the valve spring from performing this
operated thereby.
function.
`
Another object of the invention is to provide
In the usual or common valve mechanism, a
plurality of springs surround the valve stem and
operate through the ñanged head I1 and valve
ranged that the only work done by the valve
stem to return the rocker and push rod to in
spring is to close the valve, thereby permitting
the use of a lighter valve and a lighter valve 40 operative position after the valve has been opened
and closed. Obviously, with high speed engines
spring.
in which the valve is operated very fast, this
Another’cbject of the invention is to provide
puts an enormous strain on the valve stem and
an independent and self-suñîcient rocker @rm
valve spring and has necessitated the use of heav
retracting means whereby the rocker arm, push
rod and tappet will operate entirely independ 45 ier valves and heavier springs. Even withthese
changes breakdowns have been frequent. More
ently of the operation of the valve.
over, as explained above, at excessively high
Another object of the invention is to provide
speeds the inertia forces or load on the rocker
a method of balancing andretracting therocker
arm, push rod and tappet overpower the valve
arm and rocker arm operating mechanism in such
a manner that the load on the rocker arm bear 50 spring and the tappet does not follow the cam.
Also, when the valve freezes the rocker operation
ing is substantially neutralized.
_
by the valve spring is suspended.
Further objects of the invention will appear
In order to overcome this condition in the pres
from the following speciñcation taken in connec
ent invention, the rocker, push rod and push rod
tion with the drawing which form a part of this
55 operating connection are moved to their retracted
application, and in which
a method of balancing valve mechanism so ar
2,411,775
3
position or inoperative position by a ñat coiled
spring 49 having a loop 4| which engages the
rearwardly extending arm 23 of the rocker and
is coiled around the rocker hub 30, the free ends
of this spring, shown at 42, engaging a fixed
abutment 43 in the cylinder head.
It should
be noted that the spring 40 puts no load on the
4
maintains the roller 38 in engagementl with the
cam 39.
,
By reason of the method above described the
engine can be operated at much higher speeds
without danger of breakdown.
Although one specific embodiment of the in
vention has been particularly shown and de
bearings of the pin 20 but largely neutralizes the
scribed, it will be understood that the invention
load thereon. The flat coils of the spring 43
is capable of modification and that changes may
which extend around the hub 30 on opposite sides 10 be made without departing from the spirit or
of the rocker function as resilient thrust bearings
and maintain the hub and rocker centered be
scope of the invention, as expressed in the fol
lowing claim.
tween the flanges of the bushings or bearings 33
What Iv claim is:
and 34. The rocker bearing is lubricated and
In valve mechanism, a valve guide, a valve hav
the oil also lubricates the contacting surfaces of 15 ing a valve stem reciprocatable in said guide, a
the coils. This centering and thrust action is
cylinder head having spaced bearings therein, a
particularly important when the push rod block
rocker having a pivot pin mounted in said bear
35 is not disposed in the plane of the socket 2fë
ings and having an arm engaging the valve for
and the push rod 26 is not disposed in the plane
opening the valve, a spring for closing the valve,
of the longitudinal axis of the rocker arm 2l.
20 and a coil spring encircling the rocker pin and
The spring 4D takes the entire load of the
engaging the end of the rocker remote from the
rocker arm or rocker, push rod and push rod
arm engaging the valve for substantially neu
operating means and relieves the Valve spring
tralizing the inertia load of the rocker arm and
I5 from carrying this load, the sole function of
returning the rocker to its inactive position dur
the valve springl being to close the valve. Thus 25 ing the closing of the valve, said coil spring hav
the rocker Will operate entirely independently
ing ñat coils on opposite sides of the rocker and
of the valve and the tappet will always contact
between the rocker and said spaced bearings to
and follow the cam. This obviously permits the
take up thrust coaxial with the rocker pivot axis
use of a lighter valve and of a lighter valve spring.
and center the rocker between said spaced bear
The inertia forces on the rocker and push rod
are balanced by the spring 4i! which as stated
ings.
WILHELM B. BRONANDER, JR.
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